High throughput screening assay systems in microscale fluidic devices

Abstract

The present invention provides novel microfluidic devices and methods that are useful for performing high-throughput screening assays. In particular, the devices and methods of the invention are useful in screening large numbers of different compounds for their effects on a variety of chemical, and preferably, biochemical systems.

What is claimed is:  
     
       1. A method of detecting an interaction between two components of a biochemical system, comprising: 
       moving a first labeled component of the biochemical system through a first channel region;  
       moving a second component of the biochemical system through the first channel region to mix with the first component within the first channel region, whereupon the first and second components interact in a continuously flowing mixture to produce a labeled product, which labeled product has a mobility through the first channel region which is substantially equal to a mobility of the first labeled component through the first channel region;  
       moving the labeled product through a second channel region connected to the first channel region, the labeled product having a mobility through the second channel region which is different from a mobility of the first labeled component through the second channel region; and  
       detecting an amount of interaction between the first and second components by detecting an amount of labeled product in thy second channel region.  
     
     
       2. The method of  claim 1 , wherein the product has a different electrokinetic mobility from the first and second components, and the method further comprises applying an electric field along at least the second channel region. 
     
     
       3. The method of  claim 1 , wherein the first component comprises a first member of a receptor-ligand pair, and the second component comprises a second member of the receptor-ligand pair, and the product comprises a receptor ligand complex. 
     
     
       4. The method of  claim 1 , wherein the first component comprises a first member of an antibody-antigen pair, the second component comprises a second member of the antibody-antigen pair, and the product comprises an antibody antigen complex. 
     
     
       5. The method of  claim 1 , wherein the first component comprises a first nucleic acid and the second component comprises a second nucleic acid that is complementary to the first nucleic acid. 
     
     
       6. The method of  claim 1 , wherein the first component comprises a substrate, the second component comprises an enzyme and the product comprises a product of an interaction of the substrate and the enzyme. 
     
     
       7. The method of  claim 1 , wherein the product has a different charge from the first component. 
     
     
       8. The method of  claim 1 , wherein the product has a different size than the first component. 
     
     
       9. The method of  claim 1 , further comprising contacting the first and second components with a test compound, and detecting an amount of product produced with and without the test compound being present. 
     
     
       10. The method of  claim 1 , further comprising contacting the first and second components with a test compound, and detecting a decrease in an amount of first labeled component with and without the test compound being present. 
     
     
       11. The method of  claim 9 , further comprising determining an effect, if any, of the test compound on the interaction between the first and second components, by comparing an amount of product produced without the test compound being present to an amount of product produced with the test compound being present, an increase or decrease in the amount of product produced with the test compound being present being indicative that the test compound is an enhancer or an inhibitor of the interaction of the first and second components. 
     
     
       12. The method of  claim 9 , further comprising determining an effect, if any, of the test compound on the interaction the first and second component, by comparing a decrease in an amount of the first labeled component without the test compound being present to a decrease in an amount of the first labeled component with the test compound being present, a greater or lesser decrease in the amount of the first labeled component with the test compound being present being indicative that the test compound is an inhibitor or an enhancer of the interaction of the first and second components, respectively. 
     
     
       13. The method of  claim 9 , wherein the first and second components are continuously flowed through the first and second channel regions, and the test compound is contacted with the first and second components by introducing a discrete plug of the test compound into the first channel region. 
     
     
       14. The method of  claim 13 , wherein a plurality of different test compounds are separately introduced into the first channel region to contact the first and second components flowing therethrough. 
     
     
       15. The method of  claim 13 , further comprising detecting a deviation in an amount of product produced with the test compound being present relative to amount of product produced without the test compound being present. 
     
     
       16. The method of  claim 13 , further comprising detecting a deviation in an amount of decrease in a level of the first labeled component with the test compound being present relative to an amount of decrease of the first labeled component without the test compound being present. 
     
     
       17. The method of  claim 1 , wherein the second component is flowed into the first channel region from a side channel that intersects the first channel region. 
     
     
       18. The method of  claim 1 , wherein the test compound is introduced into the first channel region from a side channel that intersects the first channel. 
     
     
       19. The method of  claim 18 , wherein the side channel is fluidly connected to a pipettor capillary channel that is disposed through a capillary element that is attached to the body of the device. 
     
     
       20. The method of  claim 1 , wherein the labeled product comprises a fluorescent label. 
     
     
       21. The method of  claim 1 , wherein the first labeled component comprises a fluorescent label. 
     
     
       22. The method of  claim 1 , wherein the first component, second component and product are flowed through the first and second channel regions by pumping. 
     
     
       23. The method of  claim 1 , wherein the labeled product has a mobility in the second channel region that is faster than the mobility of the first labeled component. 
     
     
       24. The method of  claim 1 , wherein the labeled product has a flow rate that is slower than the mobility of the first labeled component in the second channel region. 
     
     
       25. A method of detecting an interaction between two components of a biochemical system, comprising: 
       providing a microfluidic device having a body and first and second interconnected channel regions disposed therein;  
       moving a first component of the biochemical system through the first channel region;  
       moving a second component of the biochemical system through the first channel region to mix with the first component within the first channel region, whereupon the first and second components interact in a continuously flowing mixture to produce a product, the product having a mobility through the first channel region which is substantially equal to a mobility of the first and second components through the first channel region; a mobility through the second channel region which is different from a mobility of at least one of the first second components through the second channel region;  
       moving the product through the second channel region; and  
       detecting the interaction of the first and second components by virtue of the different mobility of the product relative to the mobility of at least one of the first and second components through the second channel region.  
     
     
       26. A method of detecting interaction between two components of a biochemical system, comprising: 
       moving a first component of the biochemical system through a channel;  
       moving a second component of the biochemical system through the channel to mix with the first component within the channel, whereupon the first and second components interact to produce a product, the product having a mobility through the channel that is different from at least one of the first and second components; and  
       detecting the interaction of the first and second components by virtue of the different mobility of the product relative to the mobility of at least one of the first and second components.  
     
     
       27. A method of detecting an interaction between first and second components of a biochemical system, comprising: 
       providing a microfluidic device that comprises a body having at least first and second intersecting microscale channels disposed therein, the first and second microscale channels fluidly communicating with a plurality of reservoirs disposed in the body;  
       placing the first component of the biochemical system into a first reservoir of the microfluidic device;  
       placing the second component of the biochemical system into a second reservoir of the microfluidic device;  
       combining the first and second components in a mixture, the first and second components interacting in a continuously flowing mixture to produce a product, the product having a different flow rate through the microfluidic channel than the first and second components;  
       moving the mixture along the microscale channel; and  
       detecting an amount of product; within the microscale channel.